Spark-plug.



BECK..

ELUGE Mummy' ruim MAR. 17. 1910.

Paed Apr. 21, 1914.

msga@ JUNI/ILT# w/mfssfs: 7

vw i .cheaper than l engine cylinder.

. pered longitudinally from 'a point 3a near its 'UNITED srArEsrArENr oEEroE.

CHARLES W. BECK, OF ROCKY/'ILLE CENTER, NEW YORK, ASSIGNOR, BY MESNE l ASSIGNMENTS, TO MICHIGAN MOTOR SPECIALTIES COMPANY, OF DETROIT,

MICHIGAN, A. CORPORATION OF lVlICHIGrAN.I

SPARK-PLUG.

To alt 'whom t may concern l Be it known that I, CHARLES `W. BECK, a citizen of the United States, and resident of Rockville Center, county of Nassau, and State of New York, have invented certain new and useful Improvements in Spark- Plugs, of which the followingis a specifical tion.

Spark plugs in which the core is made of a sheet of'mica Vrolled lengthwise or klongitudinally 'of the core are objectionable for the reason that the rolled mica sheet flakes, that is, breaks olf in minute particles in the engine cylinder. These fiakes or particles become red hot and frequently. cause prematureexplosions in the cylinder.` A spark plug having a mica core so formed is much a core made up of small disks of mica secured to the central electrode, and for that reason are nsed, notwithstanding' the very great objection to them just mentioned. n

It is one of the main' objects of this invention to provide a spark plug having a l rolled mica core with meansto prevent the tlaking of the mica within the engine cyl- 1 inder.

Another important object of the invention l is to provide means whereby the inner por-` j tion of the base of the plug on the innerend l, of the insulator will be protected from the carbon deposit caused by the vaporization and burning of the oil within the cylinder.

In the drawings, Figure 1 is a longitudii, nal vertical sectionall View of the plug coml plete; Fig. 2 a horizontal sectional view on the line II-II of Fig. 1; Fig. 3 a perspecmoved; and Fig. 4 a view of the inner end of the plug. l

Referring to the various parts. by numerals, l designates the plug base which is threaded to adapt it tobe screwed into the Screwed into the outer end of this base is the core securing gland l 2. The core 3 is formed of sheet mica rolled,- l the folds or layers of `the mica extending 5 longitudinally of the core. This core' is ta- 1 i 'tive' view of the protecting tiring sleeve re- 1 l inner end to its outer end, and the interior of the ore securing gland islcprrespondingly tapered, and the core forced into it by coni- Specification of Letters Patent. ptented Apt 21, 1'914 Application filed March 17, f

1910. Serial No. 54%873.

pression so that said gland will rigidly hold the core in posit-ion in the base and prevent its outward withdrawal therefrom. Extending longitudinally through the core `is the central or insulated velectrode 4, said electrode being provided near its inner 'end with a-collar 5 which rests within a recess l 6 formed at. the inner end of the core. The

outer end of the core, that` is to say, that portion which project-s outwardly' beyond the securing gland, is covered and protected byv nieans of a c'ap 7, said cap'preferably being formed of porcelain. It will, of course,.be understood, however, that this cap may be The outerend of' tlie`central or insulated electrode, is threaded to receive a binding nut 8, which serves to hold the porcelain cap in position andals'o as a means Orsecuring the electrode in the core, and as a connecting device for th'egterminal wire. A. washer 9, preferably of asbestos, is interposed between vthe inner end of Athe protectingcap and the Vforined of any suitable insulating material. 7

vond the securing gland and inclosed with- ,Y

in the base, is preferably cylindrical. It will', of course, be understood, however, that. it may be of any desired shape. Fitting over and protecting this end of the core is a cap l0 of suitable insulating material,

preferably ofv porcelain. This cap' is slightlyy longer than the inner end of-the core to provide the space ll between said cap4 and the inner end of the core to allow for the unequal expansion of the cap and the core. The cap is secured'in position 4by meansof a nut 12 screwed on the electrode and bear wagsher 13, preferably of asbestos, bein fio 1.00 against the inner end of said-(jap, v9, l

terpo'setl between the end ofthe-capta y ythe i inner end of the securing gland, Thefnut.-

' of the porcelain ca nulargroove in the ,tably held within the base.

12 is provided with flexible spider arms 14, which are adapted to bear against the end and serve to prevent the nut 'racturing t e cap, and also to permit of an unequal expansion between the cap and the electrode.

Fitting within the base isa removable metallic ring cap15, saidcap being provided with a projection 16 on its outer surface adapted to snap into an internalanase, said groove being near thev inner end of the base. By this means the cap will be removably but rota- This cap is formed with an enlargement at its inner end, that is to say, the end extending into the engine cylinder, said enlargement 4forming a shoulder 17 adapted to abut againstthe inner edge ofthe base7 and the inner end of thecap is closed by a wall 18, said wall being formed with an opening '19 eccentric to the axis of the cap. Around lthe edges of this opening is secured an eyelet of' non.- -corroding metal 20 of high conductivity'. The end of the-insulated electrode projects through this opening, and of course, is eccentric to said -opening, being centrally disposed within the cap. It WilL'therefore, be seen that the electrode is-nearer one point on the margin of the eyelet than it is to all the other points on said margin. The spark will jump from said electrode to the eyelet. The -ring cap closes the inner end of the base of' the plug with the exception of the small opening 19. By this means the deposit of carbonwithin the base and on the lnsulator or core is largely prevented.

From the foregoingit is manifest that I provide an inexpenslve spark plug which will be very durable, and wherein a rolled mica core may be employed withoutl any danger of the mica flaking off within the cylinder. It is also manifest that by reason of the elicient4 protection which I provide for the core, said core will be practically indestructible. By reason of the' removable tiring cap, and the removable insulating cap for the inner end of the core, the plug may be readily cleaned. These two parts will receive all of the soot accumulation, and by removing them and replacing clean parts, the plug may be at once replaced in the cylinde'r in good working condition. The removable pa'rts may be cleaned at leisure or lentirely discarded if they are at all worn or injured. By rotating the cap in the plug a fresh 'sparking pointv may beibrought into sparking relation with-the electrode. By

provid-ing the plug with theannular groove so that the retaining proj ectidn 16 may enter lsaidgroovea't anyfpointtbe" Cappmay be readily placed in g-th'eplugand any vpoint on I the -rnar'ginj of the. eyelet 171 may vloef'brought into sparking relationwith' the electrode.

' Havingthus fullydescribed my invention,

what I claim as new and desire to secure by Letters Patent is: .i

1.A`spark plug comprising a base, a rolled mica core secured within said base, :1. porcelain cap inclosing -the inner end of v said core and protecting it from the engine gases, an electrode extending throu h'said 4core and said cap, and means on t e electrode engaging the end of the cap for yieldingly securing said cap in place.

2. A spark plug comprisingba base, an insulating core secured in said closing the inner end of said core, an electrode extending through the core land said cap, and yielding means on the electrode and engaging the cap for securing said cap in place.

3. A spark plug comprising a base, an insulating core secured in said base, a porcelain cap inclosing the inner end of said core, an electrode extending throu h the core and said cap, a nutscrewed on t e inner end of said electrode and carrying yielding fingers or spider arms adapted to bear against the inner end of the cap for yieldingly holding said cap in place.

4. A spark .plug comprising a base, a.

rolled sheet mica core extending through said base, said core being tapered outwardly, an electrode extending through'said core, a porcelain protecting cap within the base and inclosing the lmica core, a washer between the end of said cap and the base, a porcelain cap inclosing the outer end of the core, a Washer between the innerend of said cap and the outer surface of the base, the Velectrode extending throughsboth of said protecting caps, a clamp nut threaded on the outer end of said electrode, means on the electrode for engaging the inner end of the mica core, and means on the electrode for enr gaging the inner end of the inner protecting cap, whereby the core will be wedged in the base and Jthe protecting caps will be held rigidl against the base.

5. spark plug comprising a base, a rolled sheet mica c ore tapered outwardly and fitting in said base, an electrode extending through said core, a protecting cap surrounding the inner end of said core, means on the electrode to engage the inner'end of the core within the cap, meanson the electrode to engage the protecting cap and means on the outer end of the electrode for drawing said electrode outwardly and thereby wedging the core in the base and holdin the protecting captightly over the inner en of the core.-

, 6. A spark plug comprising a base, an electrode extending through said base, a removable cylindrical cap fitting; within the inner end of the base and cveing'the en# tire cylindricalinner surface; thereof, said cap being detachably held therein byreason of its elasticity Vand being eluted 'outside of the base except for an opening in its end eccentric to the electrode and through which the electrode extends, whereby the spark will be formed between the electrode and the margin of the said-opening.

7. A spark plug comprising a base, a rolled sheet mica core supported approximately midway between its ends by said base, the folds or layers of said mica sheet extending longitudinally of the core, an electrode extending longitudinally through the center of said core, a cap of insulating material x inclosing each of the projecting ends of the core, the inner ends of said caps bearing against the core support and the outer ends of lsaid caps being closed except where the electrode passes through them7 the interior of each of said caps being larger than the inclosed portionof the core, whereby there is a space within said cap to permit of an unequal expansion and contraction of the core andcaps, and means for securing the caps in place.

8. A spark plug comprising a base, a core tapered outwardly and fitting in said'base, an electrode extending through said core, a protecting cap of insulating material surrounding the inner end of said core, means on the electrode to engage the inner end of the core within thecap7 means on the electrode to engage .the protecting cap, and means on the outer end of the electrode for drawing said electrode outwardly and thereby wedging the core in the base and holding the protecting cap over theinner'end of the core.

9. A spark plug comprising a base7 an electrode extending through said base, a removable and freely rotatable c lindrical cap fitting within the inner end o the base and covering the entire inner surface thereof7 means for detachably and rotatably holding said cap in the base, the inner end of the cap being provided with an aperture eccentrically located with respect to the electrode, the margin of said aperture being at one point close to the electrode, whereby upon rotating the cap said point may be brought close to different points, on the electrode.

In testimony whereof I hereunto atx my signature in the presence of two witnesses this 16th day of March 1910.

CHARLES lV. BECK. -Witnesses:

F. R. MILLER, WM. R. DAVIS. 

